Unfortunately for both parties, his hand apparently goes straight into the woman's breast.
The shocked interview-crasher then smacks Mr Brown's arm and walks away but can be heard muttering about the unintentional grope.
Mr Brown apologised for the interruption at the end of the interview but seemed unaware that he'd touched the woman's breast.
He later took to Twitter to say his attempt to "minimise disruption" was tricky while live and in the middle of a conversation.
The accidental grope was "completely unintentional", he wrote.
Live TV can be a minefield for even the most seasoned of presenters, with countless examples of slip-ups from around the world.
Last month, ABC presenter Natasha Exelby was dumped by the public broadcaster for a gaffe that later went viral.
Ms Exelby was hosting a live weekend bulletin when she missed her cue while fiddling with a pen and made a quick but shocked recovery.